Dolphin Genes Hold Clues to Animal Intelligence

Posted by clnews Animals, Pets, Wildlife Thursday, June 28th, 2012

(LiveScience)Evolution-wise, bottlenose dolphins have left their mammalian brothers in the dust, and new research is showing what genes they changed to do it. These genes include those involved in brain and metabolism.

These changes could be why dolphins are known to be exceptionally smart, able to use tools, recognize themselves and even communicate with each other and with trainers.

“We are interested in what makes a big brain from a molecular perspective,” study researcher Michael McGowen, of Wayne State University School of Medicine in Michigan, told LiveSCience. “We decided to look at genes in the dolphin genome to see if there are similarities in the genes that have changed on the dolphin lineage and those that have changed on the primate lineage.”

The researchers compared about 10,000 genes from the bottlenose dolphin with nine other animals. (These included the cow, horse, dog, mouse, human, elephant, opossum, platypus and chicken — cows being the dolphin’s closest relatives with a sequenced genome.)

By studying its mutations, they pinpointed which genes were “evolving” or what scientists call “being selected for” — genes that underwent changes and were passed on to future generations of dolphins — by comparing them to the analogous genes from the other species. If a dolphin gene has more protein-changing mutations than the cow version, for instance, that means it was actively evolving in the dolphin population at some time.